Continuous cutting and gathering apparatus for a continuous mining machine

ABSTRACT

A gathering structure for use on the mining head of a mining machine. The mining head includes a rotary drum having helical auger flights with cutter bits mounted on their periphery. A backup panel is disposed on the mining head just rearward and parallel to the rotary drum. A gathering head is located beneath the mining head. The gathering head includes front, vertical dozer blades on each side of a central conveyor throat. The dozer blades have their bottom edge at the floor and their upper portion extends upwardly to overlap the lower portion of the backup panel. The backup panel and dozer blade cooperate to form a continuous vertical wall behind the helical flights of the rotary drum. The mine face forms a corresponding wall in front of the helical flights. The loading of the cut mined material is achieved by the helical auger flights working in conjuncture with the backup panel and dozer blades and the mine face. The panel and dozer blades are positioned immediately behind the outer helical auger sections so that with the mine face they form the walls of a screw conveyor which moves the coal to the center of the machine and onto a small pitch mat chain conveyor disposed in the central conveyor throat. The mat chain conveys the material rearwardly to conventional flight conveyors.

United States Patent 1 Arentzen 1 CONTINUOUS CUTTING AND GATHERING APPARATUS FOR A CONTINUOUS MINING MACHINE [75} Inventor: E. M. Arentzen, Charleroi, Pa.

[73] Assignee: Dresser Industries, Inc., Dallas. Tex.

[22] Filed: Nov. 5, 1973 211 Appl. No.: 412,608

Primary ExaminerErnest R. Purser Attorney, Agent, or FirmSteven R. Gustafson; John M. Lorenzen [57] ABSTRACT A gathering structure for use on the mining head of a [4 1 July 1,1975

mining machine. The mining head includes a rotary drum having helical auger flights with cutter bits mounted on their periphery. A backup panel is disposed on the mining head just rearward and parallel to the rotary drum. A gathering head is located beneath the mining head. The gathering head includes front, vertical dozer blades on each side of a central conveyor throat. The dozer blades have their bottom edge at the floor and their upper portion extends upwardly to overlap the lower portion of the backup panel. The backup panel and dozer blade cooperate to form a continuous vertical wall behind the helical flights of the rotary drum. The mine face forms a corresponding wall in front of the helical flights. The loading of the cut mined material is achieved by the helical auger flights working in conjuncture with the backup panel and dozer blades and the mine face. The panel and dozer blades are positioned immediately behind the outer helical auger sections so that with the mine face they form the walls of a screw conveyor which moves the coal to the center of the machine and onto a small pitch mat chain conveyor disposed in the central conveyor throat. The mat chain conveys the material rearwardly to conventional flight conveyors.

10 Claims, 4 Drawing Figures SHEET FIG-4 FIG-3 CONTINUOUS CUTTING AND GATHERING APPARATUS FOR A CONTINUOUS MINING MACHINE BACKGROUND OF THE INVENTION The present invention relates to mining machines and more particularly to a gathering head structure for a continuous mining machine on which the rotatable mining head is disposed transverse the forward motion of the mining machine.

A typical continuous mining machine has a mining head at the front end for cutting and breaking the material from the mine face. A gathering head is usually disposed below the mining head to collect the mined material and feed it to a conveyor which conveys it to the rear of the mining machine. From the rear of the machine the mined material is discharged to a haulage vehicle or other equipment which takes the material away from the place of the mining operation.

The gathering head typically involves gathering arms or rotating discs both of which require separate drive means and drive connections. Mining machines are perated in very harsh, wet and corrosive environments; and the gathering heads are typically required to move hundreds of tons of mined material each day. Because of the harsh nature of the operations and the large amount of work required by the mining machine, it is advantageous to reduce the number of moving parts in an attempt to minimize the amount of maintenance required.

These needs are emphasized in low seam mining operations. In low seams. the mining machine must necessarily be smaller because of the room limitations. And the machine must necessarily be lower cost because the rate of mining coal is substantially reduced due to the nature of the seam. Some prior attempts at low seam, low maintenance machines have incorporated a helical cutter head which also acts as the gathering device. These devices have eliminated gathering arms but have supplemented the action of the front helical auger with a secondary helical conveying device. Such secondary augers are disposed just rearwardly and parallel to the front auger and must incorporate additional drive means.

SUMMARY OF THE INVENTION Accordingly it is the object of the present invention to provide an improved continuous miner having a gathering head which has few moving parts.

Another object ofthe present invention resides in the provision of a continuous miner employing gathering means arranged so that the overall mining machine may be of relatively low construction.

A further object of the present invention is to provide a combination cutter head and gathering device which is relatively easy to construct and to maintain.

These and other objects of the present invention are obtained by providing a continuous miner having a front cutter head frame with a rotary cutting head rotatably mounted at its forward end. The axis of the cutting head is-disposed parallel to the face of the mine. A backup panel or auger skirt is located on the cutter head frame just rearward of and parallel to the cutting head. The cutting head has spaced left and right hand helical auger sections adapted to cut the material from the mine face and simultaneously convey the materials along the backup panel to a central position on a mat conveyor. The mat conveyor has a small pitch and is located close to the helical auger. The mat conveyor moves the material rearwardly to conventional flight conveyors positioned rearward of the may conveyor. Directly behind and adjacent to the front helical auger is a vertical dozer blade. The dozer blade overlaps a portion of the backup panel to provide a large vertical surface against which the helical auger sections may move the material.

DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of the mining machine incorporating the gathering head apparatus of the pres ent invention.

FIG. 2 is another perspective view of the mining machine shown in FIG. 1 with the mining head in the raised position.

FIG. 3 is a perspective view of the gathering head portion of the mining machine shown in FIGS. 1 and 2.

FIG. 4 is an enlarged perspective view partly in section of the mining head portion of the mining machine shown in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT A continuous mining machine 10 shown in FIGS. 1 and 2 of the drawings has a mining head 14 with a rotary drum 40 for cutting and breaking material from a mine face. Endless crawler tractor treads 16, disposed one on each side of the main frame, propel the machine. A second frame or sump frame 12 is mounted on top of the main frame II. The sump frame 12 is connected to the main frame II by means of a tongue 17 and groove (not shown) arrangement, thus enabling the sump frame to be moved horizontally away from the main frame. The sump frame 12 is moved forward and backward by a pair of hydraulic cylinders 18 located on opposite sides of the machine, one of which is illustrated. Each hydraulic cylinder I8 is connected at one end to the main frame 11 and at the other end to the sump frame. By activating the hydraulic cylinders, the rotary drum 40 is advanced or sumped into the mine face.

Because the chassis of the mining machine is configured with a central sliding sump frame, it permits the crawlers 16 to remain locked while advancing or sumping the rotary drum or augers 40 into a mine face. This design takes advantage of the fact that the static coefficient of friction between the fixed crawlers and the floor is approximately 50% greater than the dynamic coefficient of friction between moving crawlers and the floor. The hydraulic cylinders 18 act to move the sliding sump frame 12 forward. The sliding sump frame 12 carries the auger head 40, gathering head 20 and conveyor assemblies 21 and 22 in its forward and rearward movement.

The mining head 14 has two parallel support arms 30 that extend forwardly to support the rotary drum 40 at the front end of the sump frame 12 of the mining machine 10. The arms 30 are connected by a pivot structure 31 to the sump frame. A backup panel or cross member 25 is disposed at the forward end of the arms 30 just rearward of and parallel to the rotary drum 40.

The mining head 14 is pivotally mounted by the pivot structure 31 and is moved upwardly and downwardly by a pair of hydraulic cylinders (not shown) located on opposite sides of the sump frame 12. Each of these hydraulic cylinders is pivotally connected at one end to the sump frame 12 and at the other end to the arms 30.

The rotary drum 40 is driven by a pair of electric motors 34 one of which is shown in FIG. 2, that are disposed at opposite sides of the sum frame 12. The motors 34 drive motor gear transmissions and a clutch and brake mechanism 35. Each ofthe clutches is connected by means of a drive sprocket (not shown) to a drive chain 38 that delivers drive by means of a second sprocket 37 to the rotary drum.

The forward sprocket wheel is fixed to a shaft 41 which extends transversely to the arms 30. Fixed to the shaft are three auger cutting sections 42, 43 and 44. Each auger section comprises a pair of helical blades 45 having their inner peripheries fixed securely to the adjacent portion of the casing 48 of the shaft 41 and the outer peripheries of a substantial constant radial extent. The pitch of the blades 45 of each section is such that when rotated they will serve to convey the material inwardly toward the forward end of the centrally disposed conveyor 21.

The outer periphery of each helical blade 45 of each auger section 42, 43. 44 has secured thereto a plurality of spaced bit holders 46 arranged to receive bits 47 of conventional structure that extend outwardly from the periphery of the blade 45. The bits on each blade are spaced apart equally in a longitudinal or axial direction.

There is a gathering head structure 20 at the front of the mining machine structure below the arms 30. The gathering head is pivotally mounted on a pivot point 26 separate from the mining head pivot 31. The gathering head structure 20 has an apron or front deck 23 with its leading edge at the floor. The gathering head structure carries a vertical dozer blade 24 on each side of a center conveyor throat 27 and provides a deck upon which a mat conveyor chain 21 may operate. A small diameter roller foot shaft 28 is positioned very close to the front of the gathering head 20 to provide a pivot structure for the small mat conveyor 21.

The upper portion 50 of the vertical dozer blade 24 is hinged at hinge points 52 to the lower portion 51 of the blade 24. Four torsional springs 54 spring load the upper portion 50 of the blade and force it rearwardly towards the backup panel of the mining head 14, which is located immediately behind the rotating drum 40. As the rotary drum 40 is raised or lowered relative to the gathering head 20, the upper edge of the hinged dozer blade 24 remains in contact with the mining head backup panel 25.

The loading of cut mined material is achieved by the helical auger flights 42, 44 working in conjunction with the backup panel 25 and dozer blades 24 on one side and the mine floor and mine face on the other sides. The backup panel 25, the dozer blades 24, the mine floor and the mine face combine to form three exterior walls of a screw conveyor. The three walls contain the mined material within the outer helical auger flights 42, 44 so that the material may be moved to the center conveyor throat 27 of the machine 10. At this center point, the combination of the return position of the drive chains 38 and the center auger section 43 pushes the mined material back and onto the mat chain conveyor 21.

Because of the small pitch of the chain links 60 and the resulting flexible nature of the gathering chain conveyor 21, the small diameter foot shaft 28 may be used and positioned very close to the front of the gathering head 20. This permits the conveyor 21 for the mined material to be located immediately behind the center auger section 43. thus eliminating the need for auxiliary gathering apparatus.

lt is noteworthy that this gathering head design uses no moving parts. Instead the gathering structure 20 carries a pair of dozer blades 24 behind each of the outer augers 42, 44 which when working at the mine face in conjunction with the helical scrolls 45 on the auger act as a screw conveyor to move the mined material to the center conveyor throat 27 of the gathering head 20 where it is picked up by the auxiliary gathering chain conveyor 21. The gathering conveyor 21 carries the mined material about four feet to the rear where it is transferred to the rear conveyor 22. The drive for the conveyor 21 is a hydraulic motor (not shown) having appropriate drive connection means to the conveyor through the interior of the pivot structure 26.

In the illustrated embodiment, the gathering conveyor 21 comprises small, one inch pitch, cast roller chain links assembled in a conventional manner. To aid maintenance and reduce binding, the gathering chain conveyor 21 is separated into three longitudinal sections 61, 62 and 63 disposed side by side across the width of the conveyor throat 27. Each section 61, 62 or 63 is several links wide and is individually driven at its rearward end by its own pair of sprocket wheels (not shown) attached to a hydraulic motor {not shown) that is mounted in the motor port 65.

The gathering conveyor may take other forms besides a chain conveyor as long as the conveyor provides the functions necessary to the present invention. In par ticular, the conveyor 21 must be flexible enough to allow it to pivot about the relatively small diameter foot shaft 28. The smaller the diameter of the foot shaft 28 and conveyor 21, the closer it may be positioned to the front edge of the apron 23. The gathering conveyor 21 must also have the strength and speed to move the mined material rearwardly as fast as the material is fed to it by the helical blades. A flexible belt conveyor would probably fulfill the requirements of the gathering conveyor 21.

The transfer means from the gathering conveyor 21 to the discharge conveyor 22 is not shown. However, it may be of a conventional type. For the embodiment shown, the gathering conveyor 21 is simply positioned end to end with a chain and flight conveyor 22 of the type conventionally used on continuous mining machines. The end to end conveyor arrangement is effective and it provides a lower profile than an overlap arrangement would. This lower profile is important in low seam mining applications.

FIGS. 3 and 4 are included to illustrate the separate structure and relationship of the mining head 14 and the gathering structure 20. AS shown on the perspective view of FIG. 4, the mining head 14 comprises two parallel spaced apart support arms 30. The support arms 30 are connected by the horizontal pivot structure 31 to the sump frame 12. The rotary drum 40 is rotatably mounted within bearing support member 36 at the forward end of the arms 30. Power for rotating the drum 40 is transmitted from electric motors 34 through gear transmission means in the housing 35 to a rear drive sprocket (not visible) to the drive chains 38. The drive chains 38 drive forward sprocket wheels 37 that are secured to the drive shaft 41.

The backup panel or front cross member 25 extends across the front of the mining head 14 to form a substantially vertical surface behind the rotary drum 40.

FIG, 3 illustrates the gathering head structure in a perspective view that is similar to the perspective view of the mining head in FIG. 4. The gathering structure comprises a front vertical dozer blade 24 disposed on either side of a conveyor throat 27. The dozer blade 24 is substantially parallel to and overlaps the backup panel 25 to form a continuous vertical surface behind the right and left auger sections 42, 44. The surface extends from behind the upper portion of the augers downwardly.

The deck or apron 23 provides a floor in the throat 27 to support the upper flight of a gathering conveyor 60. Conveyor 60 is driven at its rearward end by means (not shown) and pivots at its forward end about a foot shaft 28.

The gathering structure 20 pivots about a pivot 26 and is raised or lowered by hydraulic cylinders (not shown) that attach at their rearward end to the sum frame 12 and at their forward end to device 33 on the gathering head 20. During a mining operation, the gathering head 20 will typically remain on the floor. The mining head 14 statutes be pivoted upwardly about the pivot 31 and then sumped into the mine face.

As the rotary drum 40 is raised. the backup panel 25 moves with it away from the dozer blades 24. To assure that no gaps form between the dozer blades 24 and the backup panel 25, the top portions 50 of the blades 24 are hinged at points 52 and are spring loaded rearwardly by springs 54. The springs 54 press the upper edges of the dozer blades 24 firmly against the backup panel 25. Thus the structure 20 assures that no gaps form between the dozer blades 24 and backup panel 25.

Having thus described the invention, those skilled in the art will recognize various uses for and changes in the details and arrangement of parts without departing from the scope of the invention as it is defined in the appended claims. It is therefore respectfully requested that the invention be interpreted as broadly as possible according to the provisions of the patent statues and limited only by the scope of the appended claims.

1 claim:

I. A low seam. continuous mining machine, comprisa main frame provided with tractor crawlers for propelling the machine;

a sump frame slidably mounted on the forward end of the main frame for movement toward a mine face while the main frame is stationary;

hydraulic means for sliding the sump frame forward of the main frame;

a mining head mounted on the forward end of the sump frame for movement therewith into a mine face. the mining head being long enough to cut a path wider than said machine and including a shaft mounted for rotation at the forward end of the sump frame and disposed transverse to the direction of movement of the sump frame;

a plurality of helical cutter members mounted about the rotatable shaft. the helical cutter members being shaped to direct mined material inwardly of the ends of the shaft;

means for rotating the shaft and associated cutter members mounted thereon;

a backup panel mounted near the forward end ofthe sump frame just rearward of the periphery of the helical cutters and substantially parallel thereto;

a gathering conveyor mounted on said sump frame and having its forward end disposed beneath and in close proximity to the mining head for gathering the mined material fed to it by the helical cutter members, said conveyor extending perpendicular to the mining head toward the rear of the machine; and

substantially vertical dozer blades disposed at each side of the conveyor just rearward of the periphery of the helical cutter members and substantially parallel thereto, the dozer blades extending upwardly to overlap the backup panel to provide a vertical surface against which the helical cutter members may move mined material inwardly to the central gathering conveyor.

2. A mining machine, comprising:

a frame mounted for horizontal movement into a mine face;

a boom mounted at the forward end of the frame for vertical movement relative to the frame;

a cutting drum rotatably mounted at the forward end of the boom on an axis of rotation disposed transverse to the movement of the frame;

means connected to the cutter drum for rotatably driving the cutter drum;

spiral auger flights mounted on the cutter drum which are shaped to move mined material towards the machine centerline during rotation of the cutter drum in a mine face;

cutter bits mounted on the periphery of the spiral flights to cut and break material from the mine face;

a gathering chain conveyor extending forwardly from the frame on the centerline of the machine to a position near the front of the mining machine just rearward of the periphery of the spiral flights for receiving mined material directly from the mining head and moving the mined material rearwardly to a discharge conveyor mounted on the mining machine; and

substantially vertical backup panels mounted at either side of the central gathering chain conveyor and disposed substantially parallel thereto and just rearward of the periphery of the spiral flights, said spiral flights being in combination with said panel effective to move the loose mined material axially along the mine head and directly onto the gathering chain conveyor.

3. A continuous mining machine, comprising:

a frame mounted for movement toward a mine face;

a rotatable mining head mounted at the front end of the frame on an axis of rotation transverse to the forward movement of the frame, said mining head being long enough to cut a path in the mine face at least as wide as said machine and comprising a plu rality of helical cutters mounted about said axis on a shaft;

means for rotatably driving said mining head;

a flexible gathering conveyor mounted on said frame such that its front end is disposed behind, below and in close proximity to said mining head, said conveyor extending generally perpendicular to the mining head and adapted to convey mined material from the mining head toward the rear of the machine;

means for driving the gathering conveyor; and

substantially vertical backup panels mounted on the frame at each side of the conveyor behind and substantially parallel with the mining head such that the panels in cooperation with the helical cutters on the mining head are effective to convey the loose mine material along the mining head directly onto the front end of the gathering conveyor.

4. A mining machine as recited in claim 3 wherein the mining head is mounted at the end of a boom pivotally connected to the main frame in a manner allowing vertical movement of the mining head relative to the gathering conveyor 5. A mining machine as recited in claim 4 wherein the gathering conveyor is pivotally mounted on the frame separate from the mining head.

6. A mining machine as recited in claim 5 wherein the gathering conveyor is located centrally of the machine and wherein the mining head includes opposed helical flights shaped to convey mined material from both ends of the mining head toward the center and onto the gathering conveyor,

7. A mining machine as recited in claim 5 further including a second conveyor mounted on the frame to the rear and in alignment with the gathering conveyor such that the gathering conveyor is movable relative to the second conveyor but adapted to convey loose mined material from the mining head onto the second conveyor.

8. A mining machine as recited in claim 3 wherein the gathering conveyor comprises a flexible mat chain conveyor.

9. A mining machine as recited in claim 8 wherein the mat chain passes around a small forward shaft giving said front end of the conveyor a low profile and allowing the conveyor to be disposed in close proximity to the mining head and the mine floor such that mined material can be conveyed directly toward and onto the conveyor.

10. A continuous mining machine as recited in claim 3 in which the mining head, the panels, and the gathering conveyor are all mounted on a sump frame which is slidably mounted on the forward end of the main frame and adapted for movement toward the mine face while the main frame remains stationary. 

1. A low seam, continuous mining machine, comprising: a main frame provided with tractor crawlers for propelling the machine; a sump frame slidably mounted on the forward end of the main frame for movement toward a mine face while the main frame is stationary; hydraulic means for sliding the sump frame forward of the main frame; a mining head mounted on the forward end of the sump frame for movement therewith into a mine face, the mining head being long enough to cut a path wider than said machine and including a shaft mounted for rotation at the forward end of the sump frame and disposed transverse to the direction of movement of the sump frame; a plurality of helical cutter members mounted about the rotatable shaft, the helical cutter members being shaped to direct mined material inwardly of the ends of the shaft; means for rotating the shaft and associated cutter members mounted thereon; a backup panel mounted near the forward end of the sump frame just rearward of the periphery of the helical cutters and substantially parallel thereto; a gathering conveyor mounted on said sump frame and having its forward end disposed beneath and in close proximity to the mining head for gathering the mined material fed to it by the helical cutter members, said conveyor extending perpendicular to the mining head toward the rear of the machine; and substantially vertical dozer blades disposed at each side of the conveyor just rearward of the periphery of the helical cutter members and substantially parallel thereto, the dozer blades extending upwardly to overlap the backup panel to provide a vertical surface against which the helical cutter members may move mined material inwardly to the central gathering conveyor.
 2. A mining machine, comprising: a frame mounted for horizontal movement into a mine face; a boom mounted at the forward end of the frame for vertical movement relative to the frame; a cutting drum rotatably mounted at the forward end of the boom on an axis of rotation disposed transverse to the movement of the frame; means connected to the cutter drum for rotatably driving the cutter drum; spiral auger flights mounted on the cutter drum which are shaped to move mined material towards the machine centerline during rotation of the cutter drum in a mine face; cutter bits mounted on the periphery of the spiral flights to cut and break material from the mine face; a gathering chain conveyor extending forwardly from the frame on the centerline of the machine to a position near the front of the mining machine just rearward of the periphery of the spiral flights for receiving mined material directly from the mining head and moving the mined material rearwardly to a discharge conveyor mounted on the mining machine; and substantially vertical backup panels mounted at either side of the central gathering chain conveyor and disposed substantially parallel thereto and just rearward of the periphery of the spiral flights, said spiral flights being in combination with said panel effective to move the loose mined material axially along the mine head and directly onto the gathering chain conveyor.
 3. A continuous mining machine, comprising: a frame mounted for movement toward a mine face; a rotatable mining head mounted at the front end of the frame on an axis of rotation transverse to the forward movement of the frame, said mining head being long enough to cut a path in the mine face at least as wide as said machine and comprising a plurality of helical cutters mounted about said axis on a shaft; means for rotatably driving said mining head; a flexible gathering conveyor mounted on said frame such that its front end is disposed behind, below and in close proximity to said mining head, said conveyor extending generally perpendicular to the mining head and adapted to convey mined material from the mining head toward the rear of the machine; means for driving the gathering conveyor; and substantially vertical backup panels mounted on the frame at each side of the conveyor behind and substantially parallel with the mining head such that the panels in cooperation with the helical cutters on the mining head are effective to convey the loose mine material along the mining head directly onto the front end of the gathering conveyor.
 4. A mining machine as recited in claim 3 wherein the mining head is mounted at the end of a boom pivotally connected to the main frame in a manner allowing vertical movement of the mining head relative to the gathering conveyor.
 5. A mining machine as recited in claim 4 wherein the gathering conveyor is pivotally mounted on the frame separate from the mining head.
 6. A mining machine as recited in claim 5 wherein the gathering conveyor is located centrally of the machine and wherein the mining head includes opposed helical flights shaped to convey mined material from both ends of the mining head toward the center and onto the gathering conveyor.
 7. A mining machine as recited in claim 5 further including a second conveyor mounted on the frame to the rear and in alignment with the gathering conveyor such that the gathering conveyor is movable relative to the second conveyor but adapted to convey loose mined material from the mining head onto the second conveyor.
 8. A mining machine as recited in claim 3 wherein the gathering conveyor comprises a flexible mat chain conveyor.
 9. A mining machine as recited in claim 8 wherein the mat chain passes around a small forward shaft giving said front end of the conveyor a low profile and allowing the conveyor to be disposed in close proximity to the mining head and the mine floor such that mined material can be conveyed directly toward and onto the conveyor.
 10. A continuous mining machine as recited in claim 3 in which the mining head, the panels, and the gathering conveyor are all mounted on a sump frame which is slidably mounted on the forward end of the main frame and adapted for movement toward the mine face while the main frame remains stationary. 